Respiratory Organs of Phylum Mollusca and Its Modification
1. Skin and mantle. 2. Molluscan gills or ctenidia or branchiae and 3. Lungs or pulmonary sac. The outer covering of the body (skin) and mantle usually act as accessory respiratory organs. 1. Skin and Mantle — as Respiratory Organs: Skin appears to be the simplest type of respiratory structure encountered in Molluscs. It acts as a respiratory organ in [...]